Interfacial engineered superelastic metal-organic framework aerogels with van-der-Waals barrier channels for nerve agents decomposition

Chemical warfare agents (CWAs) significantly threaten human peace and global security. Most personal protective equipment (PPE) deployed to prevent exposure to CWAs is generally devoid of self-detoxifying activity. Here we report the spatial rearrangement of metal-organic frameworks (MOFs) into superelastic lamellar-structured aerogels based on a ceramic network-assisted interfacial engineering protocol. The optimized aerogels exhibit efficient adsorption and decomposition performance against CWAs either in liquid or aerosol forms (half-life of 5.29 min, dynamic breakthrough extent of 400 L g−1) due to the preserved MOF structure, van-der-Waals barrier channels, minimized diffusion resistance (~41% reduction), and stability over a thousand compressions. The successful construction of the attractive materials offers fascinating perspectives on the development of field-deployable, real-time detoxifying, and structurally adaptable PPE that could be served as outdoor emergency life-saving devices against CWAs threats. This work also provides a guiding toolbox for incorporating other critical adsorbents into the accessible 3D matrix with enhanced gas transport properties.


Supplementary Tables
Supplementary Table 1. The characteristic peaks in the FT-IR spectra of the relative samples.

Supplementary Note 2:
Decontamination Test: DMMP (Sigma-Aldrich, China) decomposition was measured using a modified version of a previously described procedure. 2  There are 6 linkers (four benzoate and two formate groups). The para-carbon atoms of the benzoate groups have been frozen to mimic the rigidity of the periodic MOF structure ( Supplementary Fig. 4).

Supplementary Discussion
Intermolecular where γ is the distance between the centers of the two segments, ε is the LJ energy parameter and σ is the LJ length parameter. For successive monomers of the chain a strongly attractive FENE (finite extensibility non elastic) spring potential is added: This model has been studied extensively for chains both in the bulk, confined between walls, and under shear. The interaction between walls and segments is modelled by a pairwise LJ potential which includes the attractive tail of the potential: 12 6 ( )=4 where ν is the amount of N2 adsorbed at each equilibrium pressure, νmono is the amount adsorbed of monolayer coverage, ρ0 is the saturation pressure.
Scattering intensity derived from SAXS 8 : where I(q) is the scattering intensity, ρ1 and ρ2 are the scattering length densities of the matrix and the pores, respectively, φ is the volume fraction of pores, V is the scattering volume, γ is the radius of pores, θ is the scattering angle, λ is the wavelength of X rays, q is the scattering vector, A is the diameter of pores. The scattering intensity follows the power law in the fractal system: The performance comparison: We compared the air pressure drop at a constant velocity and the water flux driven by gravity of the published MOF composite fabrics and MNAs. As shown in Supplementary Table 3, the obtained aerogels in our research possessed a lower diffusion resistance than that of traditional MOF composite fabrics (~68% reduction in air 9 and ~52% reduction in liquid 10 ). In contrast, the superior spatial dispersion of the MNAs enabled a more accessible MOF catalyst in the hierarchical network for enhanced reagent diffusion and subsequently a faster reaction rate, highlighting the advanced concept of the proposed 3D structure of our MNAs, which is not easily obtainable by previously reported materials. In another comparison study, MNAs showed a higher liquid uptake of 8710 wt% than that of the published MOF composites (1650 wt% 11 ), which was attributed to their lower density (12 mg cm -3 ).
The high liquid uptake and simultaneous rapid decomposition make this material a promising detoxifying adsorbent for nerve agents spill. Take the detoxification of was much better than that of the published MOF composite fabrics (50 min 12 ).

Nonvolatile bases:
We propose a facile strategy to achieve the alkaline test condition by using the non-volatile alkali polymers such as polyethyleneimine (PEI) instead of the traditional aqueous solutions. We integrated the non-volatile alkali polymers into the hybrid aerogels by adding 0. 4 mmol PEI in the 100 g dispersion before freeze-drying. The obtained aerogels were denoted as PEI-MNAs. This is a significant step forward in the integration of MOFs and bases together into a porous monolith to access a catalytically active protective material, which is a popular solution for the destruction of these harmful chemicals in practical environments. Evidence of the formation of PEI-MNAs was obtained from FT-IR and XRD analysis ( Supplementary Fig. 12). The specific surface area of PEI-MNAs was estimated to be 568 m 2 g -1 . Remarkably, the catalytic performances of PEI-MNAs are comparable to the MNAs using the volatile N-ethylmorpholine solution, highlighting their potential for incorporation into protective layers against CWAs in real situations. We believe the findings pave the way for the deployment of MOF materials in personal protective equipment.